Volume 8 Issue 3 (pdf) - Andrew John Publishing Inc

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taBLe 1. Modified assessMents for patients With deMentia
Give short, simple instructions
Practice, to ensure instructions are understood
Provide prompting and encouragement
Accept a variety of responses
Get most valuable information first (i.e. minimize fatigue, agitation)
Speech testing (meaningful stimuli) more successful that PTs; SRTs more reliable
than PTTs
Obtain SATs where SRTs unobtainable
Use any speech material that is effective; meaningful/familiar speech (simple
questions or digits more successful than PBs or spondees)
Test at time of day when most alert (usually morning)
Presence of caregiver/family member may reduce agitation or anxiety
Assess over multiple sessions if needed
Include speech in noise and CAP test (s) appropriate to capability, if possible
Objective assessment; acoustic reflexes, ABR (OAEs unlikely)
of 68 years revealed that 16 out of 20
failed the Montreal Cognitive Assessment
test, indicating that they had at least mild
cognitive impairment and suggesting that
cognitive screening is warranted. Many
authors advise us that this is indeed the
case. 6–8 Assessment of cognitive status
through observation of behaviour,
history taking, screening tools, or speech
tests that address working memory and
other aspects of auditory processing and
cognitive function would be a valuable
addition to the audiologic assessment
battery. Similarly, assessment of hearing
should be part of any assessment of
cognitive function, especially since many
cognitive tests are verbal and therefore
impacted by hearing loss. Audiologists
can play an important role in the
education of other health care
professionals in this area, and provide
them with hearing screening tools and
referral criteria.
There are currently no established best
practice protocols for the audiologic
assessment of patients with cognitive
impairment. While those of us working
with elderly clients have developed our
own modifications to test procedures
(see Table 1), it would be helpful to
develop more standardized test protocols
that address the impact of cognitive
decline on patients’ ability to provide
information and the most effective ways
for us to obtain it. We should also
include new tests that provide
information about higher auditory and
cognitive processing; we need to do more
than speech testing in quiet to get
information about the entire auditory
system that will assist with management
decisions. Specialized speech tests can
provide much information about
functional communication ability, CAP
and aspects of cognitive function, and are
available in varying degrees of difficulty
to suit the ability of the patient. Dichotic
tests which target binaural integration
skills, dual tasking and memory target
both auditory and cognitive processing.
The dichotic digit test 9 is recommended
by many in the literature 10 as being the
most appropriate and cost-effective for
use with the elderly, and is currently
under trial in our clinic at Baycrest.
How does knowledge of cognitive status
change what we do Baycrest
audiologists are currently looking at
whether we modify our services based on
awareness of our patients’ cognition, with
a view to developing and integrating best
practice procedures for those with both
hearing loss and cognitive decline. We do
know that there is a great need to
provide and improve services for this
population 11,12 for whom amplification
in the form of hearing aids provides
limited benefit and poses problems for
management. Our current, technology
focused approach is not very successful
for older listeners and needs to be
resituated in a broader context of
audiologic rehabilitation (AR) because of
the important role that training and
therapy play in promoting compensatory
cognitive function. 13
Speech perception difficulties of the
elderly result from a complex interaction
of sensory and cognitive processes, and
arise from peripheral, central and
cognitive changes that occur with age.
Listening, comprehending and
communicating require more general
cognitive operations such as attention,
memory, and language representation. 14
In daily life, listeners constantly take in
bottom-up information using their
hearing, and combine it with “top-down”
knowledge that’s learned and stored in
the brain. The more difficult the listening
conditions, the more effort we have to
make to hear and understand. This
increased listening effort puts more
demands on cognitive resources needed
for other aspects of information
processing such as deriving meaning and
storing in memory. Cognitive decline
makes it harder for older listeners to
ignore, inhibit or suppress irrelevant
acoustic stimuli like music or competing
voices, and attend to the specific voice of
interest. Poorer working memory (WM)
makes it harder to fill in the gaps in
conversation, and the effort of listening
and paying attention means that older
listeners are less likely to understand and
remember what they’re hearing, even if
they hear it. 15 Focusing on the hearing
aid as a “fix” for their communication
problems misleads many clients with
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